Screwless air-conditioning coil attachment apparatus and method

ABSTRACT

An assembly and method is provided for an air-conditioning system coil housing and a plastic drain pan wherein the coil housing has one or more sheet metal walls. A first flap is cut and formed in at least one sheet metal wall which is resiliently bendable away from the metal wall. A second flap is cut and formed in the first flap. The drain pan comprises an outwardly extending lip portion such that when the coil housing is mounted to the drain pan then the sheet metal wall slidingly engages a drain pan wall whereby the first flap portion bends outwardly to catch the lip portion such that the second flap engages an underside of the outwardly extending lip portion.

This application claims benefit of U.S. Provisional Application No. 60/653,773 filed Feb. 17, 2005, which is incorporated herein in its entirety.

TECHNICAL FIELD

The present invention relates generally to air conditioning assemblies and, more particularly, to an improved assembly and method for securing an air conditioning coil to a drain pan.

BACKGROUND

After installation of an air-conditioning system, and during the lifetime of the system, it may become necessary to repair or replace the air-conditioning coil and/or drain pan. The connection between these components requires access to the interior portions of the drain pan and air conditioning coil housing. While these components can be fairly conveniently bolted together at the manufacturing plant when easier access to these interior portions of the system is available, the same easy access is normally not available once the system is installed thereby making servicing and/or replacement of these components relatively time-consuming and difficult.

Consequently, there remains a need to provide an improved attachment apparatus and method for the connection between the air-conditioning coil and the drain pan. For instance, it would be desirable to provide an improved connection assembly that would permit faster servicing and/or replacement of the drain pan or the air-conditioning coil at the installation location. If possible, it would also be desirable to provide a connection that would improve assembly times at the manufacturing plant. As well, it is necessary that the connection retain the high reliability of the existing connection therebetween.

Those of skill in the art will appreciate the present invention which addresses the above and other problems.

SUMMARY OF THE INVENTION

An objective of the present invention is an improved connection between an air-conditioning coil and the drain pan.

Another objective of the present invention is to provide a connection which is more easily serviceable after an air-conditioning system is installed.

Yet another objective of the present invention is a highly reliable connection between the air-conditioning coil and the drain pan.

These and other objectives, features, and advantages of the present invention will become apparent from the drawings, the descriptions given herein, and the appended claims. However, it will be understood that above and/or below-listed and/or other stated objectives and/or advantages of the invention and/or features of the invention are intended only as an aid in quickly understanding aspects of the invention, are not intended to limit the invention in any way, and therefore do not form a comprehensive or restrictive list of objectives, and/or features, and/or advantages.

Accordingly, the present invention provides for an attachment assembly for an air-conditioning system wherein the air-conditioning system comprises an air-conditioning coil housing and a drain pan. In one embodiment, the attachment assembly may comprise one or more elements such as, for instance, at least one receptacle wall for the drain pan which defines at least one receptacle within the air-conditioning drain pan for receiving liquids and a coil housing wall for the air-conditioning coil housing. The coil housing wall may preferably slidingly engage the receptacle wall and may extend into the receptacle on one side of the receptacle wall. A gripping arm preferably extends from the coil housing wall whereby the gripping arm is engageable with an opposite side of the receptacle wall. In a preferred embodiment, the gripping arm further defines a stop element. An enlargement or enlarged portion may be provided on the receptacle wall. The coil housing wall and the one receptacle wall mate together so that once the gripping arm is inserted over the enlarged lip portion, then the stop element prevents removal of the coil housing wall from the at least one receptacle wall due to engagement of the enlarged lip portion with the stop element.

The gripping arm may be comprised of an elastic and/or resilient material which when bent from an original shape during insertion, is then biased to return to the original shape.

In one preferred embodiment, the coil housing wall is comprised of metal and may be comprised of sheet metal. The gripping arm may then be defined by one or more cuts in the coil housing wall which permit the gripping arm to be moveable away from the coil housing wall.

As well, the stop element may be defined by one or more cuts in the gripping arm. In a preferred embodiment, the gripping arm and the stop element are also comprised of sheet metal.

If desired, the enlarged lip portion may be conveniently formed along an edge of the at least one receptacle wall and/or elsewhere on the wall. The air-conditioning drain pan may preferably define an opening therein through which access to the gripping arm is available for an operator. The operator may then be able to use only one hand with a tool, such as a screwdriver, to open the gripping arm outwardly to allow removal of the coil housing wall from the at least one receptacle wall by preventing engagement of the enlarged lip portion with the stop element.

The present invention may also comprise a method of making an attachment assembly for an air-conditioning system for securing the air-conditioner coil housing to the drain pan. The method may comprise one or more method steps such as, for example, forming an enlarged lip portion on a first wall within an air-conditioning system comprising the air-conditioning coil housing and the drain pan, providing a flexible and resilient gripping arm on a second wall within the air-conditioning system which is resiliently expandable, and providing that the first wall and the second wall are slidingly engageable whereby when the first wall and the second wall are slidingly engaged, then the gripping arm is expandable around the enlarged lip portion to thereby catch the enlarged lip portion between the resilient gripping arm and the second wall to thereby secure the first wall and the second wall together.

The method may further comprise forming an access opening in the drain pan through which the gripping arm is accessible to be bent outwardly to thereby release the enlarged lip portion from the gripping arm by bending the gripping arm away from the enlarged lip portion.

The method may further comprise forming the first wall out of sheet metal, cutting the first wall to thereby define a first flap, and bending the first flap to form the gripping arm. The method may further comprise cutting the first flap to form a second flap and bending the second flap to provide a stop surface which is engageable with the enlarged lip portion to prevent separation of the first wall from the second wall. As well, the method may further comprise providing that the second wall defines a liquid receptacle, providing that the second wall comprises a length, providing alignment surfaces adjacent opposite ends of the second wall, and/or providing that the first flap is sufficiently wide that edges of the first flap engage the alignment surfaces to prevent or reduce side-to-side movement of the first wall with respect to the second wall.

In yet another embodiment, an attachment assembly for an air-conditioning system may comprise at least one metal wall of the air-conditioning coil housing, a flap portion formed on the at least one metal wall which is resiliently bendable away from the metal wall, a receptacle wall for the drain pan to receive liquid, and/or a lip portion formed on the receptacle wall. The metal wall may be positioned such that when the air-conditioning coil housing is mounted to the drain pan, then the metal wall slidingly engages the receptacle wall whereby the flap portion bends away from the metal wall such that the lip portion is caught between the flap portion and the at least one metal wall. The first flap portion may be biased to return to an original position to engage the enlarged lip portion to thereby clamp the at least one metal wall to the receptacle wall. The second flap portion may extend outwardly from the first flap portion. The lip portion may comprise plastic material. The assembly may further comprise alignment surfaces provided on either side of the receptacle wall to resist side-to-side movement of the receptacle wall with respect to the at least one metal wall.

The same screwless attachment coupling mechanism could be used to couple other air-conditioning system components together such as the plenum, coil, plenum sections, pipes, overflow trays, and the like in a manner that is quick and convenient.

This summary is not intended to be a limitation with respect to the features of the invention as claimed, and this and other objects can be more readily observed and understood in the detailed description of the preferred embodiment and in the claims.

BRIEF DESCRIPTION OF DRAWINGS

For a further understanding of the nature and objects of the present invention, reference should be had to the following detailed description, taken in conjunction with the accompanying drawings, in which like elements are given the same or analogous reference numbers and wherein:

FIG. 1 is a side elevational view, partially in phantom, which shows an internal attachment assembly of an air-conditioning coil housing for attaching to a drain tray in accord with one possible embodiment of the present invention;

FIG. 2 is a top elevational view of an air-conditioner pan showing presently preferred locations of internal attachment assemblies in accord with the present invention;

FIG. 3 is an elevational view of a coil housing spring connector in accord with one possible embodiment of the present invention;

FIG. 4 is a side elevational view of a coil housing spring connector in accord with one possible embodiment of the present invention;

FIG. 5 is a side elevational view of a preferably plastic drain pan in accord with one possible embodiment of the present invention;

FIG. 6 is a cross-sectional view of the plastic drain pan of FIG. 5 along lines 6-6 in accord with one possible embodiment of the present invention;

FIG. 7 is a cross-sectional view of the plastic drain pan of FIG. 6 along lines 7-7 in accord with one possible embodiment of the present invention; and

FIG. 8 is an elevational view, in cross-section, showing one connection between the drain pan and the air-conditioner coil in accord with one possible embodiment of the present invention.

While the present invention will be described in connection with presently preferred embodiments, it will be understood that it is not intended to limit the invention to those embodiments. On the contrary, it is intended to cover all alternatives, modifications, and equivalents included within the spirit of the invention.

GENERAL DESCRIPTION OF PREFERRED EMBODIMENTS FOR CARRYING OUT THE INVENTION

Referring now to the drawings and, more particularly to FIG. 1 wherein an overview is provided of a presently preferred internally disposed attachment assembly 10 between air-condition coil housing 12 and drain pan 14. As indicated in FIG. 2, in general, at least two internally disposed attachment assemblies 10 may be utilized on either end of coil housing 12 at locations as indicated at 20 and 22. However, because the details of each attachment assembly 10 are substantially similar or identical except for a change in position, only one attachment assembly is discussed herein and it will be understood that the discussion applies to all such attachment assemblies.

An understanding of how internally disposed assembly 10 operates is perhaps best seen in FIG. 8 wherein an internal cross-section is provided wherein the relevant components are enlarged. Wall 16 of the coil housing preferably includes downwardly extending wall portion 24 which extends into or to the floor of water channel 18 in drain pan 14. As discussed in more detail hereinafter, wall portion 24 may preferably be comprised of sheet metal which has been stamped and/or cut out whereby gripping arm 26 is bent outwardly, preferably during the stamping/cut out process, to thereby provide for the shape of gripping arm 26 which extends outwardly from wall 16. Gripping arm 26 may be preferably shaped to provide a close fit over inner wall 28 of water channel 18 whereby the arm 26 must expand outwardly during fitting to thereby produce a biasing force which is directed inwardly.

The upper portion of inner wall 28 preferably includes enlarged lip portion 30. Drain pan 14 may preferably be made of suitable plastic, PVC, or other plastic-like material which can be molded to provide for enlarged lip portion 30. Gripping arm 26 is designed such that when gripping arm is pressed onto lip portion 30, gripping arm 26 bends outwardly or expands around enlarged lip portion 30 so as to be biased to thereby subsequently squeeze inwardly against enlarged lip portion 30. Gripping arm 26 may also be stamped, as discussed in more detail hereinafter, to provide for stop arm 32 which extends away from gripping arm 26 towards enlarged lip portion 30 and engages enlarged lip portion 30 as indicated. Once stop arm 32 engages the underside of enlarged lip portion 30, then wall 16 of the coil housing is securely attached to wall 28 of the drain pan. It will be appreciated that during installation, coil housing wall 16 may be quickly pressed over drain pan inner wall 28 whereby gripping arm 26 expands outwardly as it is pushed over enlarged lip portion 30 until stop arm 32 engages the underside of enlarged lip portion 30 to thereby provide an attachment between air-conditioning coil 12 and drain pan 14 without the need for screws, bolts, rivets, or the like.

FIG. 3 and FIG. 4 provide a more detailed view of how sheet metal wall 16 may be stamped or cut out in one presently preferred embodiment. FIG. 4 shows the final profile thereof as discussed hereinbefore. In FIG. 3, it will be seen that wall 16 is cut such as by stamping at edges 33 and 34 to form a flap in wall 16 thereby permit gripping arm 26 to be formed. Three additional cuts, namely cuts 40, 42, and 44, are also made in the so-produced flap that will become wall 16 to thereby produce another flap within a flap which will become stop arm 32.

In one presently preferred embodiment, stop arm 32 may be bent along line 46 which is defined roughly at the end of cuts 40 and 44, so that edge 48 is bent outwardly to be a stop surface for engagement with enlarged lip portion 30 as discussed above.

As well, sheet metal wall 26 is further formed by bending or inwardly pressing along region 36 at approximately the same depth as the top of edges 32 and 34. An additional bend is produced at edge 38 of the flap used to produce gripping arm 26. This additional bend provides for an outwardly directed guide surface to thereby provide that gripping arm 26 is guided to fit easily and quickly over enlarged lip portion 30.

FIG. 5 shows an elevational view of one possible embodiment of a drain pan, which in this instance might be comprised of plastic for long wear. FIG. 6 shows a cross-section thereof which may include various water passages 50 and/or various plastic support struts 52 and 54 as desired. An additional cross-section as indicated in FIG. 7 shows the interior portion where a preferred attachment assembly may be connected onto receptacle wall 28 on which is formed enlarged lip portion 30 and a lower stop surface 31 which can be engaged by stop arm 32 as discussed above. It will be noted that while enlarged lip portion 30 is formed along the upper edge of receptacle wall 28, enlarged lip portion 30 could also be positioned offset from the upper edge assuming corresponding dimensional adjustments were made to gripping arm 26 and stop arm 32.

Looking at FIG. 2 and FIG. 7, in one embodiment, center region 58 preferably comprises an opening or is an opening whereby center region 58 provides a path of entry to the interior portion at which attachment assemblies are provided at 20 and 22. Preferably, for reasons explained below, an opening is provided in either the coil housing or the drain pan for access to an interior thereof. Guide slots or other guide surfaces may be utilized to engage the sides of gripping arm 26 to prevent side-to-side movement.

To remove air-conditioning coil housing 12 from drain pan 14, it will be appreciated that a worker can insert a screwdriver through open center region 58. Then referring to FIG. 8, if the screwdriver blade is inserted into attachment assembly 10 as indicated at 56, then gripping arm 26 can be opened outwardly so that stop arm 32 no longer engages enlarged lip portion 30 thereby permitting wall 16 of coil housing 12 to be removed from wall 28 of drain pan 14. Thus, only one hand is needed to effect a release of attachment assembly 10. The ability to release attachment assembly 10 with use of only one hand can greatly facilitate removal after the system is installed, typically in a cramped space. Moreover, the connection can be made even more quickly at the manufacturing plant because it is not necessary to align several bolts and nuts and tighten the same. Instead the coil housing is snap fitted onto the drain pan in less time than it would otherwise take.

The connection is very sturdy and reliable. The connection cannot slide from side to side due to the dimensions utilized. For instance, the width of gripping arm 16 as indicated in FIG. 2 and FIG. 3 may be approximately the same as the length of wall 28. Other elements may also be provided on the coil housing and drain pan to prevent any side to side slippage.

In operation, coil housing walls 16 are formed by stamping, cutting, bending and the like as may be accomplished in working with sheet metal utilizing known sheet metal techniques. Coil housing walls 16 are then secured to the coil housing. Drain pans 14 are preferably molded utilizing molding techniques known in the art to thereby form drain pan wall 28. If metal drain pans were utilized, then other techniques could be utilized to form a roughly equivalent wall 28 preferably with an outwardly extending lip portion 30. Assembly of the air-conditioning coil housing 12 to drain pans 14 then simply requires press fitting the two components together with sufficient force to push gripping arm 16 over enlarged lip portion 30 until stop arm 32 engages lower side 31 of enlarged lip portion 30 whereupon the two elements are interlocked together. As noted above, removal requires only one hand whereby a screwdriver blade or other wedging device may be inserted to open gripping arm 16 outwardly so that the connection is released.

The screwless attachment mechanism and method disclosed herein may, if desired, be utilized to quickly couple and uncouple other air-conditioning system components together such as plenum sections, coil housing to plenum connections, overflow trays, pipes, and/or other interconnections.

Thus, the foregoing disclosure and description of the invention is therefore illustrative and explanatory of one or more presently preferred embodiments of the invention and variations thereof, and it will be appreciated by those skilled in the art that various changes in the design, organization, order of operation, means of operation, equipment structures and location, methodology, and use of mechanical equivalents, as well as in the details of the illustrated construction or combinations of features of the various elements, may be made without departing from the spirit of the invention. For instance, the attachment mechanism or similar quickly removable mechanism could be mounted to the coil housing wall instead of stamped thereon. As well, a mechanism or receiving mechanism could be mounted to the drain pan rather than molded therein. The drawings are intended to describe the concepts of the invention so that the presently preferred embodiments of the invention will be plainly disclosed to one of skill in the art but are not intended to be manufacturing-level drawings or renditions of final products and may include simplified conceptual views as desired for easier and quicker understanding or explanation of the invention. It will be seen that various changes and alternatives may be used that are contained within the spirit of the invention. Moreover, it will be understood that various directions such as “upper,” “lower,” “bottom,” “top,” “left,” “right,” “inwardly,” “outwardly,” and so forth are made only with respect to easier explanation in conjunction with the drawings and that the components may be oriented differently, for instance, during transportation and manufacturing as well as operation. Because many varying and different embodiments may be made within the scope of the inventive concept(s) herein taught, and because many modifications may be made in the embodiment herein detailed in accordance with the descriptive requirements of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense. 

1. An attachment assembly for an air-conditioning system, said air-conditioning system comprising an air-conditioning coil housing and a drain pan, said attachment assembly comprising: at least one receptacle wall for said drain pan which defines at least one receptacle within said air-conditioning drain pan for receiving liquids, a coil housing wall for said air-conditioning coil housing; a gripping arm extending from said coil housing wall whereby said gripping arm is engageable with an opposite side of said at least one receptacle wall from said coil housing wall, said gripping arm further defining a stop element; an enlarged portion on said at least one receptacle, said coil housing wall and said at least one receptacle wall mating together such that once said gripping arm is inserted over one side of said enlarged portion with said coil housing wall on an opposite side of said at least one receptacle wall, then said stop element prevents removal of said coil housing wall from said at least one receptacle wall due to engagement of said enlarged portion with said stop element.
 2. The assembly of claim 1, wherein said gripping arm is comprised of elastic material which when bent open from an original shape to be inserted over said one side of said enlarged portion is then biased to return to said original shape.
 3. The assembly of claim 2, wherein said coil housing wall is comprised of metal.
 4. The assembly of claim 2, wherein said gripping arm is defined by one or more cuts in said coil housing wall which permit said gripping arm to be moveable away from said coil housing wall.
 5. The assembly of claim 4, wherein said stop element is defined by one or more cuts in said gripping arm.
 6. The assembly of claim 5, wherein said coil housing wall and said gripping arm and said stop element are comprised of sheet metal.
 7. The assembly of claim 1 wherein said enlarged portion is formed along an edge of said at least one receptacle wall.
 8. The assembly of claim 1, wherein said air-conditioning drain pan defines an opening therein through which access to said gripping arm is available for an operator whereby an operator is able to engage and open said gripping arm outwardly to allow removal of said coil housing wall from said at least one receptacle wall by preventing engagement of said enlarged portion with said stop element.
 9. A method for making an attachment assembly for an air-conditioning system for securing an air-conditioner coil housing to a drain pan, comprising: forming an enlarged portion on a first wall within an air-conditioning system comprising said air-conditioning coil housing and said drain pan; providing a flexible and resilient gripping arm on a second wall within said air-conditioning system which is resiliently expandable; and providing that said first wall and said second wall are slidingly engageable whereby when said first wall and said second wall are slidingly engaged then said gripping arm is expandable around said enlarged portion to thereby catch said enlarged portion between said resilient gripping arm and said second wall to thereby secure said first wall and said second wall together.
 10. The method of claim 9, wherein said first wall comprises a plastic material and said second wall comprises sheet metal.
 11. The method of claim 9, further comprising forming an access opening in said drain pan through which said gripping arm is accessible to be bent outwardly to thereby release said enlarged portion from said gripping arm by bending said gripping arm away from said enlarged portion.
 12. The method of claim 9, further comprising: forming said first wall out of sheet metal; cutting said first wall to thereby define a first flap; and bending said first flap to form said gripping arm.
 13. The method of claim 12, further comprising cutting said first flap to form a second flap and bending said second flap to provide a stop surface which is engageable with said enlarged portion to prevent separation of said first wall from said second wall.
 14. The method of claim 13, further comprising: providing that said second wall defines a liquid receptacle, said second wall having a length, and providing alignment surfaces adjacent opposite ends of said second wall; providing that said first flap is sufficiently wide that edges of said first flap engage said alignment surfaces to prevent or reduce side-to-side movement of said first wall with respect to said second wall.
 15. An attachment assembly for an air-conditioning system, said air-conditioning system comprising an air-conditioning first component and a air-conditioning second component, said air-conditioning first component and said air-conditioning second components consisting of at least one of a plenum, a plenum section, a coil housing, or a drain pan, said assembly comprising: at least one first wall of said air-conditioning first component; a flap portion formed on said at least one wall which is resiliently bendable away from said wall; at least one second wall for said air-conditioning second component, a lip portion formed on said at least one second wall, said at least one first wall being positioned such that when said air-conditioning first component is mounted to said air-conditioning second component then said at least one first wall slidingly engages said at least one second wall whereby said flap portion bends away from said at least one first wall such that said lip portion is caught between said flap portion and said at least one first wall, said first flap portion being biased to return to an original position and thereby engaging said enlarged portion to thereby clamp said at least one first wall to said at least one second wall.
 16. The assembly of claim 15, further comprising a second flap portion extending outwardly from said first flap portion.
 17. The assembly of claim 16, wherein said lip portion is formed from plastic material.
 18. The assembly of claim 16, wherein said second flap is positioned to engage said lip portion to thereby secure a coil housing wall and at least one receptacle wall together.
 19. The assembly of claim 16, further comprising alignment surfaces provided on either side of said at least one second wall, said first flap comprising outer edges that engage said alignment surfaces to resist side-to-side movement of said at least one receptacle wall with respect to said at least one metal wall. 